Problem: Khan.scratchpad.disable(); To move up to the maestro level in his piano school, William needs to master at least $165$ songs. William has already mastered $37$ songs. If William can master $4$ songs per month, what is the minimum number of months it will take him to move to the maestro level?
Answer: To solve this, let's set up an expression to show how many songs William will have mastered after each month. Number of songs mastered $=$ $ $ Months at school $\times$ Songs mastered per month $+$ Songs already mastered Since William Needs to have at least $165$ songs mastered to move to maestro level, we can set up an inequality to find the number of months needed. Number of songs mastered $\geq 165$ Months at school $\times$ Songs mastered per month $ +$ Songs already mastered $\geq 165$ We are solving for the months spent at school, so let the number of months be represented by the variable $x$ We can now plug in: $x \cdot 4 + 37 \geq 165$ $ x \cdot 4 \geq 165 - 37 $ $ x \cdot 4 \geq 128 $ $x \geq \dfrac{128}{4} = 32$ William must work for at least 32 months.